In general, artificial marble is used as a material for kitchen furniture, plastic bath, tables, interior articles, etc, because it has many advantages in beautiful pattern and color, good processability, and lighter weight compared with natural marble.
The acrylic artificial marble is prepared with a mold by injecting a resin mixture and then curing the injected resin. The resin mixture is prepared by adding additives of a filler such as aluminum hydroxide, magnesium hydroxide and calcium hydroxide, pigments, curing agents, initiating agents, releasing agents, dispersing agents, etc to a resin syrup of methyl methacrylate (MMA) and polymethyl methacrylate (PMMA).
The most important technical feature for preparing artificial marble is to provide natural pattern and color thereon. Accordingly, intensive research and efforts have been made to achieve the purpose in the field of artificial marble industry.
U.S. Pat. No. 5,837,175 discloses a process for producing artificial marble by curing liquid resins in a molding cell, which comprises a step in which liquid resins each having different color are laminated by injection in the molding cell and a comb-like tool is moved in the liquid resins laminated while the blades of the tool are in contact with the bottom of the molding cell.
Japanese Patent Laid-open Nos. 10-323848 and 11-277552 disclose a process for preparing an artificial marble with natural pattern and color by laminating at least one resin layer with different color on a liquid resin layer ununiformly dispersed with pigments, and using a comb-like tool with different needles and gaps.
Japanese Patent Laid-open No. 11-291267 discloses a process for preparing an artificial marble with natural pattern and color by using a comb-like tool with a means for dispersing liquid resin.
Further, Japanese Patent Laid-open No. 1-291268 discloses an apparatus for preparing an artificial marble with natural pattern and color, which comprises a moving mold cell, a means for feeding liquid resin, and a comb-like tool, wherein the means for feeding liquid resin are equipped with two exit nozzles and a mixer for mixing liquid resin and pigments without agitation.
However, the above-mentioned patent applications provide with artificial marbles with stripe pattern but not good natural pattern and color.
Accordingly, the present inventors have developed a new process for producing artificial marble with natural pattern and color to overcome the shortcomings of the prior artificial marbles.